Hello Laurent, jnh1201,
@Laurent - thanks for that solution! Turning off the UDP discovery also did the trick for me. Began working right away!
I wanted to also add some interesting details from my experience.
I have a small raspberry pi cluster cluster and was running the driver on one of them. From my laptop i was attempting to use the admin gui and failing to connect. Since the laptop i am using is a work machine it has firewall set up and i assumed it was a firewall issue. As a test of this i attempted to have a node connect to the driver from my laptop. To my surprise it worked fine.
I looked at the config for the node, expecting to find that its default is to *not* do UDP discovery- but, no, it also uses that.
So I guess that maybe the node is 'smart' enough to go ahead with the explicit host/port if they're in the config file (jppf-node.properties), but the admin gui isn't?
I'd be curious if anyone can explain the difference in behavior - I'd just like to understand. It's working now, so I'm going to go and play with my raspberry pi cluster, but if anyone has a comment i'd be interested....
(and thanks again to Laurent Cohen for all his work in developing JPPF!)